Last post on Feb 23, 2012 at 1:05 PM
You are in the Chevrolet Blazer
What is this discussion about?
Chevrolet Blazer, GMC Jimmy, SUV
#18 of 27 Re: Blower motor intermitently works [bpetite]
Jan 25, 2010 (12:45 am)
It is not the relay! It is your ignition switch! By ignition switch, I mean the wire cluster in the steering wheel that goes down to the fuse block the floor panel/fire wall. $100 bucks at Advance Auto. Trust me, that is what it is. It will slowly begin to deteriorate more and your dash lights will stop coming on, then your day runners wont appear when you turn the key on etc... Oh, by the way, when your blower is running intermittently, your windows wont go down and your brake light and ABS light in your dash will flash on and off like it is doing a systems check at initial start up. IGNITION SWITCH! Not the relay. I used to tap my middle relay and make everything work again, too! Everybody thinks its that cause of that very maneuver.
#19 of 27 Re: Blower motor intermitently works [bitter]
Jan 24, 2011 (1:58 pm)
Nice find! I have the same symptoms in my daughters car. When, you say ignition switch, I assume yo mean the electrical switch that the key operates. Does the switch have a harness that goes all the was to the fuse panel or do you need to buy a switch and the harness? Any special tricks to replace that component?
#20 of 27 Blower Motor Intermittantly Runs
Sep 27, 2011 (10:15 am)
I have a 1997 Chevy Blazer 4.3L. I have a new blower motor, interior fan switch, resistor, and AC components. I have 2 issues: 1) The blower motor intermittantly cuts out. 2) The highest speed does not work-it stays the same speed as the 3rd position. The windows and everything else work just fine and no lights come on the dash as some people have posted on here.
Regarding the blower motor cutting out, I can unplug the plug on the outside of the blower motor casing (the plastic box it sits in) on the bottom left corner from the plug coming from the wiring harness. I can usually unplug it then plug it back in and it will work for a few mins before cutting out intermittantly then quitting altogether. Everyone tells me it's the resistor but I have replaced that already. The plug looks to be in good shape and I have cleaned the connectors to be sure it is making the best connection possible. When I wiggle the plug it does not cut out so it seems to be fitting nice and tight. It is almost as if unplugging it and plugging it back in resets it somehow? But only temporarily. What am I missing?
Regarding the 4th positon of the blower speed switch: I have replaced the switch and positions 1, 2, and 3 all work properly but when clicked into the 4th and final position, nothing changes. It remains the same speed at position 3.
Can anyone help me? I'm pulling my hair out over this!
#21 of 27 Re: Blower Motor Intermittantly Runs [leatherneck99]
Sep 27, 2011 (10:28 am)
I would replace the A.C. blower motor relay.
ACDelco 15-8719 or 15-5635 (GM 12193601)
#22 of 27 Re: Blower Motor Intermittantly Runs [duntov]
Sep 27, 2011 (10:48 am)
Which relay is that? There are 3 on the firewall and the repair book I have does not specify which one does what. I attempted to do that a few weeks ago but thought I'd have to replace all 3 because I do not know which one of the three is the right one.
I did however buy one and replace them 1 at a time and couldn't get the blower to come on at all so I returned the relay.
#23 of 27 Re: Blower motor intermitently works [lfe357]
Feb 22, 2012 (9:21 am)
Did you find the answer? I have a 2008 Cobalt Sport with the same problems you all mention about intermitten blower fan and lights. I also suspect the "ignition cluster" whatever that is. What exactly needs to be replaced?
#24 of 27 Re: Blower motor intermitently works [alzheimer]
Feb 22, 2012 (10:36 am)
Yes, it was the ignition starter swith. Cost about $100 to get the AC-Delco part at RockAuto.com. My part number was D1498C. All the wierd problems went away! It comes with a wiring harness that easily ties into the existing harness. Youn need to open up the steering column to get at the switch which connects to the mechanical device that you turn with the key.
#25 of 27 Re: Blower motor intermitently works [alzheimer]
Feb 22, 2012 (10:48 am)
New ignition switch solved this problem plus others such as cruise control.
#26 of 27 Re: Blower motor intermitently works [lfe357]
Feb 23, 2012 (12:15 pm)
About cruise control-- I do think it is somehow connected to the electric problems. Also, it seems that when I remotely start the Cobalt, the fan quits but unsure. It didn't work for days until one morning I start the car via the key in ignition and the fan worked. Seems like a consensus and I should replace the ignition start switch but may be a different part number for the Cobalt. Thanks so much.
#27 of 27 Re: Blower motor intermitently works [alzheimer]
Feb 23, 2012 (1:05 pm)
The cruise control leads could also run through the ignition switch. When you see the wiring harness for that switch you can see that it handles many connections. When the switch goes bad, everytime you use it there is a chance for a connection to open up or reconnect so the problems appear to be random.